In the riveting second volume of Paulsen's crime trilogy (after Night Rituals ), Denver freelance reporter Tally Janrus, covering the murder and mutilation of a young boy, learns from his police detective friend that the boy had been sexually abused by several men and that there are at least six other killings in the area with the same MO. Tally's friend has been abruptly taken off the case, a sure signal that someone higher up doesn't want it solved. A ``journalist'' who kills nasty stories for fees from his victims warns Tally off the case and is fatally shot; Tally's girlfriend, Kari, is molested. Interspersed with Tally's ongoing investigation are glimpses of the abduction and ``training'' of nine-year-old Davey by a national ring of child-molesters (and killers). Tally finally gets his story and his revenge, but the resolution is in the hands of an old Mexican-American with an ancient rifle. No matter that Tally is not prime mover: Paulsen, a Newbery Award-winning writer of YA novels, delivers a narrative rich in detail, swift in plot and impossible to put down. (Aug.)